YAG Laser system

Abstract

A reliable, low cost, light weight, CW pumped Nd:YAG laser with optional Q-switching is provided with a rail for the laser optics that isolates the optical axis from movement of the laser head housing. A laser pot is provided with a housing and quickly detachable cover both molded of a resin that is impervious to water, optically opaque, possesses low thermal deformation, high dielectric strength and resistance to damage by light and UV radiation. The pot is formed with a cavity lined by molded reflectors and divided by a septum interposed between the laser rod and lamp. The lamp is removable with the cover and is readily coupled with the lamp sockets designed for accepting variations in lamp manufacturing tolerances. The power supply for the laser resonator is transformerless and parallel triggering is employed for the lamp. The cooling system is provided with a water immersed heat exchanger defined by a coated copper tube that prevents ionic action.

What is claimed is: 
     
       1. A reliable, light weight, low cost YAG laser comprising: a resonator cavity including a YAG rod and two mirrors, a lamp for exciting the rod, a laser pot comprising a housing containing the rod and lamp, and a detachable cover for the housing and means for connecting said cover to said housing, said pot housing including connection means for detachably connecting the ends of said lamp, said connection means including a conical socket receiving one end of the lamp and a cylindrical socket receiving the other end of the lamp, the cover including light spring means for receiving the lamp while permitting its mounting in the housing on the sockets and for removal therefrom as the cover is removed from the housing;   a power supply means coupled with the resonator for supplying power to the resonator; and   a cooling system coupled with the resonator for cooling the resonator.   
     
     
       2. A reliable, light weight, low cost YAG laser in accordance with claim 1 and further including: a septum in said cover for separating said resonator cavity between the lamp and rod, and molded reflectors in said resonator cavity for the lamp and rod, the reflectors being molded elliptical resin members coated with gold.   
     
     
       3. A reliable, light weight, low cost YAG laser in accordance with claim 1 wherein: one of the mirrors of said resonator cavity forms an integral part of the rod and the other mirror being spaced from the rod and being adjustable, a mirror mounting block supporting the adjustable mirror, serves as its own tool for adjusting, rotating and removing the mirror.   
     
     
       4. The invention in accordance with claim 3, wherein a mirror mounting block supports the adjustable mirror, and serves as its own tool for adjusting, rotating and removing the mirror. 
     
     
       5. The invention in accordance with claim 4, wherein the mirror mounting block supports the adjustable mirror, a polarizer and a shutter supported by the mounting block. 
     
     
       6. The invention in accordance with claim 5, wherein the geometric center of the adjustable mirrors located off the optical axis of the laser rod permits the mirror to be rotated such that a new reflecting surface can be brought into position. 
     
     
       7. A reliable, light weight, low cost CW pumped Nd:YAG laser comprising: a compact laser head unit for generating a laser output comprising an optical resonator including a Nd:YAG rod and two mirrors, a lamp for exciting the rod, a laser pot for mounting the rod and the lamp, the pot comprising a housing containing the rod and lamp and a detachable cover for the housing and means for connecting the cover to the housing, and the pot housing being molded from a resin material that is impervious to water, optically opaque, low thermal deformation, high dielectric strength and resistance to damage by light and UV radiation, the pot including a lamp and laser rod parallel triggering means for the lamp, water means for cooling the lamp and rod, means for providing a flow path over the lamp and rod;   a power supply means coupled with the resonator for supplying power to the resonator; and   a cooling system coupled with the resonator for cooling the resonator.   
     
     
       8. A reliable, light weight, low cost CW pumped Nd:YAG laser in accordance with claim 7 and further including: a quick disconnect means for connecting the cover to the housing in a liquid tight and light tight manner and for permitting the cover to be quickly removed from the housing for a quick lamp change.   
     
     
       9. The invention in accordance with claim 7, wherein the resin is a mineral loaded phenolic resin. 
     
     
       10. The invention in accordance with claim 7, wherein a septum is between the lamp and rod and separate the cavity therebetween into a path for the water to flow over the lamp and rod. 
     
     
       11. A reliable, light weight, low cost CW pumped Nd:YAG laser comprising: a compact laser head unit for generating a laser output comprising a resonator, a housing, a rigid rail, a laser resonator mounted on the rail, and connecting means for connecting the rail to the housing so that the rail and consequently the optical axis of the resonator and the laser is substantially insensitive and independent of any distortion or elongation of the housing, the connecting means including three connectors for the rail to the housing, the first connector permitting vertical movement of the rail relative to the housing, the second connector permitting vertical movement and lateral movement normal to the optical axis of the rail relative to the housing and the third connector longitudinal movement along the optical axis and rotational movement along the optical axis of the rail relative to the housing;   a power supply means coupled with the resonator for supplying power to the resonator; and   a cooling system coupled with the resonator for cooling the resonator.   
     
     
       12. The invention in accordance with claim 11, wherein the laser includes a Q-switch mounted on the rail for providing high peak power pulses. 
     
     
       13. A reliable, light weight, low cost CW pumped Nd:YAG laser, in accordance with claim 12 wherein: said cooling system includes a reservoir containing substantially pure demineralized and deionized water, means for hydraulically coupling the reservoir with the resonator, and a heat exchanger immersed in the reservoir and having flowing therein cooling liquid, the heat exchanger including copper tubing and a coating on the exterior of the tubing for isolating the copper of the tubing from the pure water and thereby prevent ionic action therewith.   
     
     
       14. A reliable, light weight, low cost CW pumped Nd:YAG laser, in accordance with claim 12 wherein: the power supply comprises a lamp and current means for supplying current to the lamp, parallel triggering means for providing a stepped-up triggering pulse to the lamp and a transformerless circuitry, isolation means isolating the triggering pulse from the current that ignited the lamp and further isolating high level drive signals to the resonator.   
     
     
       15. The invention in accordance with claim 11, further including a transductor having a sensing end and a feedback end, an optical coupler coupled with the transductor, the isolation means isolating the sensing end and the feedback end. 
     
     
       16. The invention in accordance with claim 11, wherein the power supply is a non-isolated transformerless convertor.